Let's Encrypt Static CT logs & RFC 6962 EOL.

[Matthew McPherrin]

Hello CT Enthusiasts and begrudging ,

Let's Encrypt has applied to the CT log programs with our static CT logs, based on Sunlight.

You can find metadata about these logs via the logs themselves, at:

https://log.sycamore.ct.letsencrypt.org/

https://log.willow.ct.letsencrypt.org/

As well, we have a test instance at

https://log.twig.ct.letsencrypt.org/

We intend to transition our RFC6962 logs to read-only in the future. Other CAs should be prepared to begin using these logs. You can find more information in a blog post we published today at https://letsencrypt.org/2025/08/14/rfc-6962-logs-eol

Thanks, Matthew.